A major study has linked melatonin use to a 90% higher risk of heart failure — raising urgent safety questions about the ”natural” sleep aid.

A large-scale retrospective study presented at the American Heart Association’s Scientific Sessions has challenged the widespread perception of melatonin as a completely harmless, “natural” sleep remedy.

By analyzing the medical histories of over 130,000 adults diagnosed with chronic insomnia, researchers compared those who took melatonin for at least one year with a closely matched control group of non-users.

Over a five-year tracking period, individuals who used melatonin long-term were found to have an 89% higher hazard of developing heart failure, a threefold increase in heart-failure-related hospitalizations, and a doubling of all-cause mortality compared to those who did not take the supplement.

While these dramatic findings have sparked significant concern, medical experts urge caution, emphasizing that the observational study shows an association rather than direct causation. The study relied on electronic health records, which means researchers could not account for critical factors such as precise dosages, the severity of participants’ underlying sleep disorders, or potential mental health conditions that might independently elevate cardiovascular risk. Because over-the-counter melatonin is highly popular and largely unregulated in the United States, cardiologists advise patients to consult with healthcare professionals to evaluate and address the root causes of their sleep struggles rather than relying indefinitely on daily supplementation.

source: American Heart Association. (2025). Effect of Long-term Melatonin Supplementation on Incidence of Heart Failure in Patients with Insomnia. Circulation.

Sweet Dreams
Melatonin Use Linked to Massively Increased Risk of Heart Failure
“Melatonin supplements may not be as harmless as commonly assumed.”
https://futurism.com/health-medicine/melatonin-heart-failure-cardiovascular-health?fbclid=IwdGRjcAUJ-FJjbGNrBQn4G3Bkb2YFZXh0bgNhZW0CMTEAc3J0YwZhcHBfaWQMMzUwNjg1NTMxNzI4AAEeCjHSFaJOsbkymzPpnr1eRyUuvFSOo27WXfMFdMSAB1gKJCT0nNjw0tJC7OM_aem_OhnvVdqYnxnDH4SfM_4gjg

If you’re one of the many people chowing down on melatonin gummies to help get to sleep, you may want to check out this study.

A new piece of research published by the American Heart Association made an alarming discovery about long-term use of melatonin supplements, an over-the-counter sleep aid used by tens of thousands. Basically, those who use melatonin over a year or more had a 90 percent higher risk of developing congestive heart failure over a five-year period.

Before you go flush your gummies down the toilet, there are a few caveats. For starters, the findings weren’t based on a clinical trial, but on data from a large database of anonymous health records. Researchers drew from data on chronic insomniacs, specifically, splitting them into two groups: those who have dosed the sleep-regulating hormone over a period of 12 months or more, and those who suffer without.

Still, the results are clearly worrisome. Overall, the study found that 4.6 percent of the melatonin group went on to develop heart failure, compared to 2.7 percent for the control group.

That wasn’t the only data point suggesting it may be time to ween off the ‘tone. A secondary analysis performed by the researchers found that melatonin users were nearly 3.5 times more likely to be hospitalized for heart failure than those in the other group, with hospitalization rates of 19.0 and 6.6 percent, respectively.

“Melatonin supplements are widely thought of as a safe and ‘natural’ option to support better sleep, so it was striking to see such consistent and significant increases in serious health outcomes, even after balancing for many other risk factors,”

For decades, the answer to “how much sleep does an adult need?” has been simple: eight hours. The idea dates back to the mid-19th century when the notion of eight hours of work, eight for recreation and eight for sleep first took hold.

But growing evidence suggests that eight hours may not be the ideal amount of sleep for everyone, as a new narrative review in Brain Medicine reminds us.

In one early study, researchers found that people in Tanzania, Namibia and Bolivia slept for between 5.7 and 7.1 hours a night. These short sleep durations can’t be attributed to traffic noise, social media use or too much artificial light at night.

The short nights also seemed to be enough: people did not make up for them with long daytime naps. Without an alarm clock, they tended to wake close to dawn, regardless of the day of the week.

But one recent analysis estimated the average to be 6.4 hours.

So, is eight hours too much? These studies make an important assumption that the amount people naturally sleep is the amount they need. That assumes that hunter-gatherers are free from stress, busy schedules and other pressures on sleep. But is that really the case?

But other evidence has emerged from large studies looking at the relationship between sleep and health in industrialised societies.

If we define optimal sleep as the amount linked to the best health, many large studies suggest the sweet spot may be less than eight hours. One recent study used brain and body scans and molecular measures to look at how sleep relates to the ageing of different organs. It estimated the optimal amount to be between 6.4 and 7.8 hours, depending on the person’s sex and the organ being studied.

Many studies find that both too little and too much sleep are linked to poorer health, including heart disease, stroke, cognitive decline and obesity. But scientists are still debating whether too much sleep causes poor health or is instead an early sign of it. Either way, these findings challenge the idea that everyone needs exactly eight hours and suggest that consistently sleeping for much longer may be worth paying attention to.

However, all these estimates of optimal sleep duration are based on averages, and the average person does not exist. When given enough opportunity to sleep, studies find that young adults sleep longer than healthy older adults. Even people of the same age can need very different amounts of sleep.

Current sleep duration recommendations, from the National Sleep Foundation in the US, reflect these individual differences. It says that adults aged 26 to 64 should get between seven and nine hours of sleep per day, but that sleeping between six and ten hours may be appropriate for some adults. That is a long way from the one-size-fits-all eight-hour rule.

Most of us do not wake naturally before dawn. Many of us have short sleep during the working week and longer catch-up sleep on work-free days.

Artificial light is recognised as the main driver of this shift. It changes our sleep habits and delays our body clock, which controls the timing of sleep and wakefulness.

Irregular sleep is also common, particularly among shift workers and university students. Irregular sleep is linked to poorer health. But if you lose sleep during the week, catching up on some of it at the weekend appears to be better than not catching up at all – even though it makes your sleep pattern less regular. So regularity matters, but so does the total amount of sleep you get over a week or longer.

The eight-hour rule is clearly too simple. People need different amounts of sleep, and when we sleep matters too. But one simple message remains: get enough sleep when you can, wherever you can, and don’t worry too much about the occasional bad night.

Tuoreen tutkimuksen mukaan terveydelle parasta olisivat 6-8 tunnin yöunet.

Tutkimuksen mukaan riittämätön uni voi verottaa elinkaaren pituutta jopa raskaammin kuin huono ruokavalio, yksinäisyys tai vähäinen liikkuminen, jotka pitkään ikään myös vaikuttavat.

Yksittäisistä elämäntapoihin liittyvistä tekijöistä tupakointi näyttää edelleen olevan kaikkein eniten elinvuosia vähentävä tapa.

Tutkijoiden mukaan ihmisen pitäisi nukkua vähintään seitsemän tuntia yössä parantaakseen oloaan ja edellytyksiään elää pitkään.

Tutkimus tehtiin tarkastelemalla valtavaa tietokantaa, jossa oli elämäntapoihin liittyvää tietoa.

– Ihmisten todellakin kannattaisi pyrkiä nukkumaan joka yö seitsemästä yhdeksään tuntia, kiteytti tutkija Andrew McHill.

niapnea voi lisätä Parkinsonin taudin riskiä, ilmenee tuoreesta tutkimuksesta. CPAP-laitteen käyttö saattaa kuitenkin vähentää sairastumisriskiä, kirjoittaa New York Times.

Tutkimusartikkeli aiheesta on julkaistu JAMA Neurology -tiedelehdessä.

Obstructive Sleep Apnea, Positive Airway Pressure, and Implications of Early Treatment in Parkinson Disease
https://jamanetwork.com/journals/jamaneurology/fullarticle/2841763